Spring lock



Nov. 4, 1969 G. E. w. LEWIN 3,476,426

SPRING LOCK Filed March 14, 1966 2 Sheets-Sheet. 1

Nov. 4, 1969 G. E. w. LEWIN 3,476,426

SPRING LOCK Filed March 14, 1966 2 Sheets-Sheet 2 United States Patent ()2 U.S. Cl. 292-76 1 Claim ABSTRACT OF DISCLOSURE A spring lock for use in latching a cupboard door or the like in a closed position comprises a mounting plate fastened to the door, the mounting plate including a base and two laterally spaced upstanding supports between which a spring bolt operates. The spring bolt one end of which is integral with the base includes an upwardly and forwardly extending portion which merges into an acutely curved portion that cooperates with, and is retained by, a lock plate secured to the door frame. The spring bolt terminates in a backwardly extending end portion 'provided with laterally extending pins which are slidingly engaged in corresponding grooves provided on the inner faces of'the-upstanding supports.

This invention relates to locks adapted for cupboard doors, trap doors and the like and refers particularly to a spring lock manufactured in one piece.

Spring locks of various types are widely in use for locking cupboard doors and the like. Most of these locks are provided with two or more mounting holes rendering possible their screwing on the support. At present, the doors are manufactured in many cases of very hard materials, such as laminated plastic sheets and the like, wherein the screws are very hard to mount without predrilled holes. For such doors the conventional locks are not suitable at all. In most cases, one hole is made already during the manufacture of the door for inserting the mounting screw of the handle knob therein, but normally no more holes are provided. The material is of such a hardness that it involves considerable difliculties to drill the necessary holes at the application place of the cupboard.

The conventional spring locks comprise a plurality of separate parts which makes their manufacture relatively expensive and their handling complicated.

The present invention has as its object to overcome the shortcomings of conventional locks of thin type by producing a spring lock substantially comprising a spring bolt portion and a mounting portion. The lock according to the invention is characterized in that the bolt portion and the mounting portion are made in one single piece, the bolt portion comprising a resilient portion projecting from the mounting portion, which resilient portion includes an acute-curved section or is provided on one side with a bead, said bolt portion being adapted to be bent inwards against the mounting portion in order to be locked with its free end in a suitable manner to the mounting portion.

The spring lock according to the invention is further characterized in that the mounting plate proper is provided with a single, preferably oblong aperture rendering possible the mounting by the mounting screw of the handle and at the same time as the handle.

The invention is described in a greater detail in the following, reference being had to the accompanying drawings showing some embodiments of the invention.

FIG. 1 shows in a schematic manner a side-view of "ice the lock according to the invention after the manufacturing process.

FIG. 2 shows a horizontal view of the lock seen from above, the bolt portion being bent inwards against and locked to the mounting portion.

FIG. 3 shows a longitudinal section through the lock according to FIG. 2.

'FIG. 4 shows a cross-section through the lock according to FIG. 2.

FIG. 5 shows by a sectional side elevation the lock according to FIGS. 1-4 rigidly mounted on a door together with the handle.

FIGS. 6-8 show another embodiment of the invention, the acute-curved section of the bolt portion being provided with a roller.

FIG. 9 shows a third embodiment of the invention, the belt, portion extending directly from the mounting plate and formed at its outer section with side flanges the inner surfaces of which are provided with projections engaging with the inner section of the bolt portion.

. @JFIG. 10 shows the outer section of the bolt portion in the embodiment according to FIG. 9, a roller being mounted between the flanges.

.As appears from FIGS. 1-5 the entire lock according to. the invention is manufactured in one single piece of a resilient material, for example plastics, and comprises substantially a mounting portion 1 and a spring bolt portion 2. The section of the mounting portion which abuts to the support is designed as a mounting plate 3 and provided with an oblong screw hole 4. Two parallel lateral supports 5 upwardly extending from the mounting plate 3 are connected along the one end by a section 6 of the bolt portion 2 upwardly projecting from the mounting portion. The section of the bolt portion which projects from the upper portion of the lateral supports 5 is resilient and formed with an acute-curved section 7 or a bead.

The free outer end of the bolt portion comprises laterally projecting pins 8 adapted to be inserted from below into locking grooves 9 in the inner surfaces of the lateral supports 5.

In order to make the mounting portion 1 after its screwing by only one screw remaining fixed in the desired position, the mounting plate 3 is on its lower surface provided with a plurality of stubs or the like adapted to engage with the support, as appears, for example, from FIG. 3.

In the door-frame a lock-plate 14 of known type is mounted against which the acute-curved section or bead 7 of the bolt portion shall strike and slide thereon.

FIG. 5 shows the spring lock according to the invention rigidly mounted on a cupboard door 10 by means of the mounting screw 12 for the handle 11, for which screw a hole 13 was prepared already during the manufacture of the door.

In the very hard cupboard doors as they are now made of laminated plastic sheets or the like it is extreme- 1y difficult to drill the holes needed for the mounting screws of a lock on the application piece of the cupboard. For this reason, the manufacturers provide the door with a hole for the handle which always is required already during the manufacture of the door.

When using the lock according to the present invention no further mounting holes are required in addition to said hole for the handle. As a result thereof, the mounting is substantially easier and cheaper.

FIGS. 6-8 show a somewhat modified embodiment of the invention wherein the curved section 7 of the bolt portion on the surface facing the mounting portion 1 is provided with recesses 15 adapted to carry the shaft of a small roller 16. Said roller projects through an opening 17 in the bolt portion 2 to contact the locking plate when the door is being closed.

FIGS. 9 and 10 show a further modified embodiment of the invention wherein the mounting plate 3 has no lateral supports and the bolt portion extends directly from the plate. The inner section 18 of the bolt portion 2 projects a distance upwards from the mounting plate 3, is thereafter bent obliquely outwards and has U-shaped cross-section, the flanges 19 being directed downwards. The inner surfaces of the flanges 19 are provided with projections 20 adapted to engage with the upwardly directed section 18 of the bolt portion for limiting the spring movements of the bolt.

Between the flanges 19 in the outer section of the bolt portion a roller 21 may be suspended such that it can rotate freely. In this embodiment it is, thus, not only the bent upper section of the bolt portion which is resilient, but the entire upwardly directed section of the bolt portion can participate in the springing, if desired.

The mounting plate 3 according to the present invention may, of course, be designed in conventional manner with laterally projecting mounting wings 22 (FIG. 2) comprising several screw holes.

. The spring lock according to the invention operates as. follows: Upon hitting the locking plate 14 the outermost section of the bolt portion 2, i.e. the curved section or bead 7 slides downwards along the locking plate, whereby the upper bolt portion between the section 7 and the mounting at the lateral supports is bent somewhat so that the section 7 can spring inwards, while the pins 8 at the outer end of the bolt portion slide in grooves 9 in the lateral supports. After having passed the top of the locking plate, the section 7 springs out again and locks the door in closed position.

' In the modified embodiment according to FIGS. 9

and '10 the springing of the bolt portionwill instead commence already at its mounting in the mounting plate. Due to the stronger springing, this embodiment is adapted for use in such cases when compensation for a swelling and shrinking of the dooris'required.

I claim: I

1. A spring lock for use in latching a cupboard door or the like in a closed position comprising a mounting plate structure including a base portion adapted to be secured to the door, two laterally spaced support portions upstanding from said base portion and between which a spring bolt operates, said spring bolt having one end thereof integral with said base portion and including an upwardly and forwardly extending portion which merges into an acutely curved.portion-that cooperates with and is retained by a locking plate adapted to be secured to the door frame, the other end of said spring bolt terminating in alower and backwardly extending portion provided with laterally extending pins which are slidably engaged in corresponding grooves provided on the inner faces of said upstanding support portions to permit resilient movement of said acutely curved portion relative to said locking plate.

References Cited UNITED STATES PATENTS I 3/1911 Lee 292-76 R. L. WOLFE, Assistant Examiner 

